Suzhou No. 4 Pharmaceutical Factory

An HPLC method for the determination of dihydro-α-aminophenylacetic acid in finished product and reaction mixture was described.Nucleosil C₁₈ column and mobile phase of 0.1 mol/L KH₂PO buffer (pH 4.0) were used.The detection wavelength was 210 nm.The linear range was 0.1-2 mg/mL.Its related substance (α-aminophenylacetic acid and tetrahydro-α-aminophenylacetic acid) were simultaneously determined

Clindamycin phosphate gel was determined by HPLC.The interference from excipients was eliminated by pretreatment of the sample and adjusting the mobile phase.A satisfactory recovery of 99.6% was obtained with an RSD of 0.7%.